<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="https://cdn.jsdelivr.net/npm/vue@2.6.14/dist/vue.js"></script>
   
    <style>
        *{
            margin: 0;
            padding: 0;
        }
        .nav{
            margin: 0 auto;
            display:flex;
            flex-direction: row;
            height: 100px;
            line-height: 100px;
            justify-content: flex-start;
            flex-wrap:wrap;
           border: 10px black solid;
           overflow:auto;
        }
        li{
            height: 100px;
            width: 100px;
            text-align: center;
            list-style: none;
        }
        li:nth-of-type(odd){
        }
        li a{
            text-decoration: none;
            font-family: 'Franklin Gothic Medium', 'Arial Narrow', Arial, sans-serif;
            font-style: normal;
            font-size: 14px;
            color:#be6666;
            display: block;
        }
        li a:hover{
            background-color: rgb(162, 255, 255);
            
        }
        div:after{
    position: absolute;
    width: 0px;
    height: 0px;
    content: " ";
    border-right: 100px solid #ff0;
    border-top: 100px solid transparent;
    border-left: 100px solid transparent;
    border-bottom: 100px solid transparent;
}
        
    </style>
</head>
<body>
    <ul class="nav">
        <li><a href="#">yyf</a></li>
        <li><a href="#">zhou</a></li>
        <li><a href="#">yyf</a></li>
        <li><a href="#">zhou</a></li> 
        <li><a href="#">yyf</a></li>
        <li><a href="#">zhou</a></li> 
        <li><a href="#">yyf</a></li>
        <li><a href="#">zhou</a></li> 
        <li><a href="#">yyf</a></li>
        <li><a href="#">zhou</a></li>
    </ul>
    <div id="root">{{a}}</div>
    <script>
        const data = {
            a:"123"
        }
        console.log(data)
        vm = new Vue({
            el:'#root',
            data
        })
        console.log(data)
       new Promise(function() {
  console.log(1);
});

setTimeout(function() {
  console.log(2);
});

console.log(3);
console.log('string'instanceof String)
    </script>
</body>
</html>